阅读说明：本技术 包括带有渐缩延伸部的套圈的馈通组件 (Feedthrough assembly including ferrule with tapered extension ) 是由 M·J·桑德斯 P·B·阿莫特 S·E·戈德曼 S·J·鲁滨逊 B·C·蒂申多夫 于 2018-05-09 设计创作，主要内容包括：在一些示例中,一种馈通组件包括套圈,该套圈包括基部部分以及从该基部部分延伸的至少一个突起；电容滤波器,该电容滤波器定位成与套圈的基部部分相邻,使得电容滤波器的外壁面向套圈的至少一个突起的内壁；导电引脚,该导电引脚延伸穿过套圈中的孔和电容滤波器中的孔；以及导电材料,该导电材料在套圈的至少一个突起的内壁与电容滤波器的外壁之间,该导电材料将套圈和电容滤波器电耦合,以使电容滤波器接地,其中,套圈的至少一个突起的内壁和电容滤波器的外壁是渐缩的。(In examples, a feed-through assembly includes a ferrule including a base portion and at least protrusions extending from the base portion, a capacitive filter positioned adjacent to the base portion of the ferrule such that an outer wall of the capacitive filter faces an inner wall of the at least protrusions of the ferrule, a conductive pin extending through the hole in the ferrule and the hole in the capacitive filter, and a conductive material between the inner wall of the at least protrusions of the ferrule and the outer wall of the capacitive filter, the conductive material electrically coupling the ferrule and the capacitive filter to ground the capacitive filter, wherein the inner wall of the at least protrusions of the ferrule and the outer wall of the capacitive filter are tapered.)

1, a feedthrough assembly, the assembly comprising:

a ferrule comprising a base portion and at least projections extending from the base portion;

a capacitive filter positioned adjacent to the base portion of the ferrule such that an outer wall of the capacitive filter faces an inner wall of the at least protrusions of the ferrule;

a conductive pin extending through a hole in the ferrule and a hole in the capacitive filter; and

a conductive material between the inner walls of the at least protrusions of the ferrule and the outer walls of the capacitive filter, the conductive material electrically coupling the ferrule and the capacitive filter to ground the capacitive filter,

wherein the inner walls of the at least protrusions of the ferrule and the outer walls of the capacitive filter are tapered relative to each other such that a gap between the inner walls of the at least protrusions of the ferrule and the outer walls of the capacitive filter decreases as one progresses from a top of the at least protrusions to the base portion of the ferrule.

2. The assembly of claim 1, wherein the at least protrusions extending from the base portion are tapered such that a width of the at least protrusions increases as one progresses from a top of the at least protrusions to the base portion of the ferrule.

3. The assembly of claim 1, wherein the at least projections extending from the base portion are tapered such that the inner wall extends from the base portion of the ferrule at an angle greater than 90 degrees.

4. The assembly of claim 1, wherein the conductive material comprises a solder reflow.

5. The assembly of claim 1, further comprising a thin film on an inner wall of the at least protrusions of the ferrule, the thin film configured to wet solder during reflow.

6. The assembly of claim 1 wherein said at least protrusions of said ferrule include a th fin protrusion, said th fin protrusion having an inner wall facing a th portion of said outer wall of said capacitive filter, and a second fin protrusion having an inner wall facing a second portion of said outer wall of said capacitive filter.

7. The assembly of claim 6, wherein the -th and second fin projections are tapered such that a width of each fin projection increases as one progresses from a respective top of the fin projection to the base portion of the ferrule.

8. The assembly of claim 1, wherein the at least projections comprise a single continuous projection.

9. The assembly of claim 1, wherein the single continuous protrusion surrounds the capacitive filter.

10. The assembly of claim 1, wherein the single continuous protrusion partially surrounds the capacitive filter.

An implantable medical device of the species , the device comprising:

a housing defining an opening; and

a feedthrough assembly disposed in the opening and attached to the housing, wherein the feedthrough assembly comprises:

a ferrule comprising a base portion and at least projections extending from the base portion;

a capacitive filter positioned adjacent to the base portion of the ferrule such that an outer wall of the capacitive filter faces an inner wall of the at least protrusions of the ferrule;

a conductive pin extending through a hole in the ferrule and a hole in the capacitive filter; and

a conductive material between the inner walls of the at least protrusions of the ferrule and the outer walls of the capacitive filter, the conductive material electrically coupling the ferrule and the capacitive filter to ground the capacitive filter,

wherein the inner walls of the at least protrusions of the ferrule and the outer walls of the capacitive filter are tapered relative to each other such that a gap between the inner walls of the at least protrusions of the ferrule and the outer walls of the capacitive filter decreases as one progresses from a top of the at least protrusions to the base portion of the ferrule, an

Wherein a hermetic seal is formed between the ferrule and the housing at the opening.

12. The apparatus of claim 11, wherein the at least protrusions extending from the base portion are tapered such that a width of the at least protrusions increases as one progresses from a top of the at least protrusions to the base portion of the ferrule.

13. The device of claim 11, wherein the at least projections extending from the base portion are tapered such that the inner wall extends from the base portion of the ferrule at an angle greater than 90 degrees.

14. The apparatus of claim 11, wherein the conductive material comprises a solder reflow.

15. The apparatus of claim 11, further comprising a thin film on an inner wall of the at least protrusions of the ferrule, the thin film configured to wet solder during reflow.

16. The apparatus of claim 11, wherein said at least protrusions of said ferrule comprise an th fin protrusion, said th fin protrusion having an inner wall facing a th portion of said outer wall of said capacitive filter, and a second fin protrusion having an inner wall facing a second portion of said outer wall of said capacitive filter.

17. The apparatus of claim 16, wherein said -th and second fin projections are tapered such that a width of each said fin projection increases as one progresses from a respective top of said fin projection to said base portion of said collar.

18. The apparatus of claim 11, wherein the at least projections comprise a single continuous projection.

19. The apparatus of claim 18, wherein the single continuous protrusion surrounds the capacitive filter.

20. The apparatus of claim 18, wherein the single continuous protrusion partially surrounds the capacitive filter.

Technical Field

The present invention relates to an electrical feedthrough for an implantable medical device.

Background

For example, Implantable Medical Devices (IMDs) such as implantable stimulation devices, implantable sensing devices, cardiac pacemakers, implantable cardioverter/defibrillator (ICD) and neuromodulators may use or more electrical feedthroughs to establish electrical connections between circuitry within the implantable medical device and leads, electrodes, or sensors external to the device within the patient's body.

Disclosure of Invention

In examples, the disclosure relates to a feedthrough assembly and techniques for forming the feedthrough assembly.

The ferrule may include a base portion and at least protrusions (e.g., or more fins) extending from the base portion. to electrically couple the outer surface of the capacitive filter and the inner surface of the protrusions of the ferrule, a conductive material may fill the gap, for example, by reflowing the conductive solder into the gap between the inner surface of the protrusions and the outer surface of the capacitive filter.

In aspects, the disclosure relates to a feed-through assembly comprising a ferrule comprising a base portion and at least protrusions extending from the base portion, a capacitive filter positioned adjacent to the base portion of the ferrule such that an outer wall of the capacitive filter faces an inner wall of the at least protrusions of the ferrule, a conductive pin extending through the hole in the ferrule and the hole in the capacitive filter, and a conductive material between the inner wall of the at least protrusions of the ferrule and the outer wall of the capacitive filter, the conductive material electrically coupling the ferrule and the capacitive filter to ground the capacitive filter, wherein the inner wall of the at least protrusions of the ferrule and the outer wall of the capacitive filter are tapered relative to each other such that a gap between the inner wall of the at least protrusions of the ferrule and the outer wall of the capacitive filter decreases as one progresses from a top of the at least protrusions to the base portion of the ferrule.

In another aspect, the present disclosure is directed to a IMD comprising a housing defining an opening, and a feedthrough assembly disposed in the opening and attached to the housing, wherein the feedthrough assembly comprises a ferrule comprising a base portion and at least protrusions extending from the base portion, a capacitive filter positioned adjacent the base portion of the ferrule such that an outer wall of the capacitive filter faces an inner wall of the at least protrusions of the ferrule, a conductive pin extending through the hole in the ferrule and the hole in the capacitive filter, and a conductive material between the inner wall of the at least protrusions of the ferrule and the outer wall of the capacitive filter, the conductive material electrically coupling the ferrule and the capacitive filter to ground the capacitive filter, wherein the inner wall of the at least protrusions of the ferrule and the outer wall of the capacitive filter taper relative to each other such that a gap between the inner wall of the at least protrusions of the ferrule and the outer wall of the capacitive filter decreases as one progresses from a top of the at least protrusions to the base portion of the ferrule, and wherein a hermetic seal is formed between the opening and the housing.

In another aspects, the present disclosure is directed to a method for forming a feedthrough assembly, the method comprising positioning a capacitive filter adjacent to a base portion of a ferrule such that an outer wall of the capacitive filter faces an inner wall of at least protrusions, the at least protrusions extending from the base portion of the ferrule, the inner wall of at least protrusions of the ferrule and the outer wall of the capacitive filter being tapered relative to each other such that a gap between the inner wall of at least protrusions of the ferrule and the outer wall of the capacitive filter decreases as one progresses from a top of at least protrusions to the base portion of the ferrule, wherein the filter assembly comprises a conductive pin extending through a hole in the ferrule and a hole in the capacitive filter.

Further details of one or more examples are set forth in the accompanying drawings and the description below other features, objects, and advantages of the invention will be apparent from the description, from the claims, and from the drawings.

Drawings

Fig. 1-3 are diagrams respectively illustrating front, side, and top views of an exemplary feedthrough assembly according to the present disclosure.

Fig. 4 is a view showing a sectional view taken along line a-a of fig. 3.

Fig. 5 is a diagram illustrating an example of a tapered ferrule protrusion adjacent to a capacitive filter of the example feedthrough assembly of fig. 1-3.

Fig. 6 and 7 are diagrams illustrating solder reflow into the gap between the capacitive filter of fig. 5 and the tapered ferrule protrusion.

Fig. 8 is a diagram illustrating another examples of tapered ferrule protrusions adjacent to a capacitive filter according to the present disclosure.

Fig. 9 and 10 are diagrams illustrating views of an exemplary ferrule with tapered protrusions (or "fins") for an exemplary feedthrough assembly including an 11-pin array.

Detailed Description

At , an Implantable Medical Device (IMD) such as, for example, an implantable stimulation device, an implantable sensing device, a cardiac pacemaker, and an implantable cardioverter/defibrillator (ICD) employs a feedthrough assembly to establish an electrical connection between circuitry within the implantable medical device and a lead, electrode, or sensor external to the device within the patient.

Fig. 1 is a front view of an exemplary feedthrough assembly 10, feedthrough assembly 10 includes an inward side 18 and an outward side 20, fig. 2 illustrates a side view of feedthrough assembly 10 of fig. 1, fig. 3 illustrates a top view of the feedthrough assembly, showing the inward side 18 of feedthrough assembly 10, fig. 4 illustrates a cross-sectional view of feedthrough assembly 10 along section a-a shown in fig. 3, the terms "inward," "inward," etc. may generally refer to a direction toward an interior of an electronic device (e.g., IMD) when assembly 10 is incorporated into an electronic device when used herein with respect to feedthrough assembly 10, conversely, the terms "outward," "outward," etc. generally refer to a direction toward an exterior of the IMD when assembly 10 is incorporated into an electronic device when used herein with respect to feedthrough assembly 10.

As shown in fig. 1-4, feedthrough assembly 10 includes a ferrule 12, an array of feedthrough pins 16 (only pins 16 are labeled in fig. 1), and a capacitive filter 14. The ferrule 12 includes a base portion 24 and a protrusion 26 extending from the base portion 24. Fig. 4 shows that individual feedthrough pins (e.g., pin 16) of the array extend from an inward side 18 of feedthrough assembly 10 to an outward side 20 of feedthrough assembly 10 through respective holes in ferrule 12 and capacitive filter 14. An insulator 28 (e.g., a ceramic insulator such as glass) electrically isolates the feedthrough pin 16 from the ferrule 12, and may also provide a hermetic seal between the inward side 18 and the outward side 20. Each feedthrough pin 16 is formed of an electrically conductive material that provides a conductive path from an inward side 18 to an outward side 20 of feedthrough assembly 10, for example, to deliver electrical stimulation or sense electrical signals in the case of an IMD or other medical device. Although the exemplary assembly 10 includes a feedthrough array having three feedthrough pins, any number of feedthrough pins in the feedthrough array is contemplated, such as a 9-pin or 11-pin array.

The ferrule 12 may be configured to mount to or within a housing of an electronic device, such as an IMD in some examples of , the ferrule 12 may include a flange or other mechanical feature that facilitates mounting the ferrule 12 to or within a housing of an electronic device.

In examples, the ferrule 12 includes a material that facilitates mounting the ferrule 12 to a housing of an IMD, for example, the IMD housing may include titanium or a titanium alloy and the ferrule 12 may include titanium or a titanium alloy that can be welded to the IMD housing, examples of materials from which the ferrule 12 may be formed include nickel, titanium alloys such as titanium 6Al-4V or titanium-vanadium, platinum, molybdenum, zirconium, tantalum, vanadium, tungsten, iridium, rhodium, rhenium, osmium, ruthenium, palladium, silver, and alloys, mixtures, and combinations thereof.

The feedthrough assembly 10 may be used in an IMD or other medical device, in some cases such electronic devices may be subject to electromagnetic interference (EMI) that interferes with the proper operation of circuitry within the IMD. thus, the feedthrough assembly 10 includes a capacitive filter 14 to address EMI, for example, the capacitive filter 14 may be configured to act as a low pass filter that transmits relatively high frequency electromagnetic signals to ground (e.g., to the housing of the IMD via the ferrule 12) and relatively low frequency signals to circuitry within the IMD.

The feedthrough assembly 10 includes a conductive material 22 that electrically couples the ferrule 12 to the capacitive filter 14 to ground the filter 14. for example, the conductive material 22 may be in contact with plating on an outer surface of the filter 14 that is electrically coupled to or more conductive plates within the filter 14 that are configured to be grounded. additionally, the conductive material 22 may also mechanically couple the ferrule 12 to the capacitive filter 14. As shown in FIG. 2, for example, the conductive material 22 is located between the ferrule protrusion 26 and the capacitive filter 14. the conductive material 22 may be any suitable solder. as described in the next step , the conductive material 22 shown in FIG. 2 may be deposited by reflowing solder paste, solder ribbon, or other suitable material into the gap between the inner surface of the protrusion 26 and the opposing outer surface of the filter 14. any suitable solder material may be used, such as, for example, tin-lead solder.

Fig. 5 is an enlarged view of the feedthrough assembly 10 of fig. 1-3, showing of the protrusions 26 (the left-hand protrusion 26 shown in fig. 2) extending from the ferrule base portion 24 to a height H at the top of the protrusions 26, and showing the portion of the adjacent capacitive filter 14. for purposes of description, a view of the assembly 10 is shown in fig. 5 in which there is no conductive material 22 in the gap 42 between the inner surface 30 and the outer surface 32 of the capacitive filter 14.

As shown in fig. 5, the inner wall 30 of the protrusion 26 and the outer wall 32 of the capacitive filter 14 are tapered relative to each other such that the gap 42 between the inner wall 30 of the protrusion 26 and the outer wall 32 of the capacitive filter 14 decreases as one progresses from the top of at least protrusions to the base portion 24 of the ferrule 12, for example, as shown in fig. 5, the protrusion 26 is tapered such that the inner wall 30 tapers from a width W2 adjacent the base portion 24 of the ferrule 12 to a smaller width W1 at the top of the protrusion 26. the taper of the inner wall 30 may be represented as an angle a of less than 90 degrees as shown in fig. 5 where the outer wall 32 of the capacitive filter 14 is substantially perpendicular to the upper surface of the base portion 24 of the ferrule 12, the width of the gap 42 decreases from W3 adjacent the top of the protrusion 26 to W4 at the surface of the base portion 24.

In some aspects of , for example, the inner surface 30 of the protrusion 26 and the outer surface 32 of the filter 14 may be described as being non-parallel to each other as compared to a case where the inner surface 30 extends from the base portion 26 according to the dashed line shown in fig. 5 such that the inner surface 30 of the protrusion 26 and the outer surface 32 of the filter 14 are parallel to each other.

Any suitable values may be selected for the parameters shown in fig. 5 (e.g., W1, W2, W3, W4, H, and angle a), which may depend on the overall design of feedthrough assembly 10 and the electronic device in which assembly 10 is to be used. The width W1 may be about 1 mil to about 20 mils, such as, for example, about 5 mils. The width W2 may be greater than W1, and may be about 5 mils to about 30 mils, such as, for example, about 15 mils. The height H may be about 25 mils to about 60 mils, such as, for example, about 40 mils to about 60 mils or about 50 mils. The width W3 may be selected based on the size of the solder preform used for reflow (e.g., W3 is selected so that the reflow may at least specifically sit within a top gap having a width of W3). W3 may be about 2 mils to about 20 mils. The width W4 may be greater than zero, such as about 2 mils, or may be zero (e.g., as shown in fig. 8, there is no gap between the inner surface 30 and the outer surface 32 at the base portion 24). The angle a may be less than 90 degrees, such as, for example, about 80 degrees to about 84 degrees. Other values than the above parameters may be considered.

Examples of the present disclosure may be manufactured using any suitable technique. As shown in fig. 6 and 7, a solder material, such as a strip of solder material, may be placed in the upper gap between the top of the protrusion 26 and the outer wall 32 of the filter 14. In this configuration, a hollow cavity 34 is defined between the protrusion 26 and the filter 14. The solder material may be reflowed into the cavity body 34, for example, in an inert gas, to form a solder 38, which solder 38 electrically couples the ferrule 12 and the filter 14 to ground the filter 14.

In examples, a thin film may be deposited onto the inner surface 30 of the protrusion 22 prior to the reflow process using any suitable deposition technique the thin film may be deposited prior to positioning the filter 14 adjacent the protrusion 26 and may improve wetting of the solder during reflow.

The tapered nature of the protrusion 26, the tapered nature of the gap 42, and/or the non-parallel orientation of the inner surface 30 and the outer surface 32 of the protrusion 26 may improve the manufacturability of the feedthrough assembly 10, for example, by depositing a thin film on the inner surface 30 as described herein and adequately grounding the capacitive filter 14. As a example, the tapered configuration of the protrusion 26 improves the thin film application technique by having the inner surface 30 with a non-perpendicular face for visual processing (e.g., sputter deposition). As a second example, the overall thickness of such a thin film may be increased and/or the rate at which the thickness of the thin film is increased. due to the tapered nature of the protrusion 26 and/or the tapered nature of the gap 42, even when the width W4 is zero, a void volume such as the cavity 34 in FIG. 6 may be used for solder placement. as a result of the example and the second example, solder 38 achieves a high footprint between the inner surface 30 of the protrusion 26 and the outer surface 32 of the filter 14. thus, the grounding of the filter 14 may be improved or at a desirable level, which may provide desired array of the feedthrough assembly 10 with improved performance losses .

As noted above, although the assembly 10 is described herein as including a 3-pin feedthrough array, examples are not so limited. For example, fig. 9 and 10 show a ferrule 40 having two tapered protrusions (also referred to as tapered fins), which ferrule 40 may be used in an assembly including an 11-pin feedthrough array in the manner described herein.

Although the example assembly 10 described herein includes a ferrule 12 that includes two tapered protrusions (also referred to as tapered fins), examples are not so limited.for example, the ferrule may include tapered protrusions or more than two tapered protrusions in some examples the ferrule may include a single continuous tapered protrusion that completely or partially surrounds the outer wall of an adjacent capacitive filter, e.g., as an elongated circle or horseshoe.

Various examples have been described. These and other examples are within the scope of the following claims.